An under bump metallurgy structure and wafer structure using the same and method of manufacturing wafer structure are provided. The under bump metallurgy structure includes an adhesion layer, a barrier layer and a wetting layer. The adhesion layer is disposed on a bonding pad of a wafer. The barrier layer is disposed on the adhesion layer. The wetting layer is disposed on the barrier layer. The adhesion layer, the barrier layer and the wetting layer are respectively made of nickel with boron, cobalt and gold.
Legal claims defining the scope of protection, as filed with the USPTO.
1. An under bump metallurgy (UBM) structure, comprising: an adhesion layer disposed on a bonding pad of a wafer, wherein the adhesion layer is made of nickel with boron (Ni—B); a barrier layer disposed on the adhesion layer, wherein the barrier layer is made of cobalt (Co); and a wetting layer disposed on the barrier layer, wherein the wetting layer is made of gold (Au).
2. The under bump metallurgy structure according to claim 1 , wherein the adhesion layer and the barrier layer are electroless plated layers individually.
3. The under bump metallurgy structure according to claim 1 , wherein the wetting layer is an electroless plated layer or an immersion plated layer.
4. The under bump metallurgy structure according to claim 1 , wherein the thickness of the adhesion layer is approximately 1˜15 μm.
5. The under bump metallurgy structure according to claim 1 , wherein the thickness of the barrier layer is approximately 0.15˜7.5 μm.
6. The under bump metallurgy structure according to claim 1 , wherein the thickness of the wetting layer is approximately 0.05˜0.15 μm.
7. A wafer structure, comprising: a wafer; a bonding pad disposed on the wafer; a passivation layer covering the wafer and exposing a part of the bonding pad; and an under bump metallurgy structure, comprising: an adhesion layer disposed on the bonding pad, wherein the adhesion layer is made of nickel with boron; a barrier layer disposed on the adhesion layer, wherein the barrier layer is made of cobalt; and a wetting layer disposed on the barrier layer, wherein the wetting layer is made of gold.
8. The wafer structure according to claim 7 , wherein the adhesion layer and the barrier layer are electroless plated layers individually.
9. The wafer structure according to claim 7 , wherein the wetting layer is an electroless plated layer or an immersion plated layer.
10. The wafer structure according to claim 7 , wherein the thickness of the adhesion layer is approximately 1˜15 μm.
11. The wafer structure according to claim 7 , wherein the thickness of the barrier layer is approximately 0.15˜7.5 μm.
12. The wafer structure according to claim 7 , wherein the thickness of the wetting layer is approximately 0.05 ˜0.15 μm.
13. The wafer structure according to claim 7 , wherein the structure further comprising: a bump disposed on the wetting layer.
Cooperative Patent Classification codes for this invention. Click any code to explore related patents in that topic.
May 9, 2008
September 21, 2010
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